The following account of the prior art relates to one of the areas of application of the present application, hearing aids.
In recent years, ear level Hearing Aid FM receivers with frequency synthesis for RF channel selection have been presented to the market place.
With integrated frequency synthesis in the FM receivers, simple effective robust ways for changing the receiving frequency channel were required. The current methods for changing the receiving channel are presented in the following.
Today there are basically two different methods
1. Pushbutton
2. Wireless
Some FM receivers like the Oticon R2 have a separate button, where the user with a push can either                Single-step between the channels; or        Automatically seek for the next channel with a signal.        
This functionality is illustrated in FIG. 1.
One disadvantage of the above approach is that, it may be time consuming to find the appropriate channel.
Changing the receiving channel by utilizing a wireless connection to the receiver is presently done either                by means of a fixed programmer installed at the door of a room, e.g. the wall pilot from Phonak or the eZync from Oticon.        or by means of a handheld device, e.g. Inspiro from Phonak or T20/T21/WRP/T30/T31 from Oticon.        
This functionality is illustrated in FIGS. 2a and 2b, respectively.
WO 2010/086462 A2 describes a method for operating a hearing device that is worn by a user, the method comprising the steps of receiving a transmission signal comprising an audio signal of a sound source, determining a distance between the sound source and the hearing device, and generating an output signal supplied to an output transducer of the hearing device by at least taking into account the audio signal of the transmission signal and the distance.
US 2010/0104120 A1 describes a hearing aid intended to be able to recognize acoustic situations more reliably, the hearing aid including a microphone device for picking-up a sound signal, a reception device for picking-up an electrical or electromagnetic signal and a classification device for determining an acoustic situation from the signals of the microphone device and the reception device. A signal processing device processes the signals of the microphone device and the reception device as a function of an output signal of the classification device. In particular, the signals of the microphone device and the reception device are made available separately to the classification device for recognizing the situation. Thus, the individual input signals, or the correlation thereof, can be used for recognizing the situation.